<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>QQ号</title>
</head>

<body>
    <script>
        var str = "这是我的QQ：666666，您的QQ是：123456，马化腾的QQ是：100000"
        var a = /[1-9]\d{4,9}/g;
        var aa = str.match(a)
        console.log(aa);
    </script>
</body>

</html>